Long-lost continent found under Indian Ocean

Sand from Mauritian beaches reveals rock from ancient landmass

Published: 02/27/2013 at 5:09 PM

(Nature) The drowned remnants of an ancient microcontinent may lie scattered beneath the waters between Madagascar and India, a new study suggests.

Evidence for the long-lost land comes from Mauritius, a volcanic island about 900 kilometres east of Madagascar. The oldest basalts on the island date to about 8.9 million years ago, says Bjørn Jamtveit, a geologist at the University of Oslo. Yet grain-by-grain analyses of beach sand that Jamtveit and his colleagues collected at two sites on the Mauritian coast revealed around 20 zircons — tiny crystals of zirconium silicate that are exceedingly resistant to erosion or chemical change — that were far older.